Method of increasing the plasticity of portland cement mixtures



106. cowosmows, p comma R PLASTlC L flmmJ Patented Feb. 16, 1943 2,311,289

UNITED STATES PATENT OFFICE W METHOD OF INCREASING THE PLASTICITY OF PORTLAND CEMENT MIXTURES Robert Ben Booth, Springdale, Conn., assignor to American Cyanamid Company, New York, N. Y., a corporation of Maine No Drawing. Application May 21, 1940,

Serial No. 336,360

2 Claims. (01. 106-92) This invention relates to a method of increascreases in plasticity, but the material itself is ing the plasticity of Portland cement mixtures. extremely cheap so that practically no additional One of the serious problems in the concrete cost is added to cement plasticized with the black industry lies in the lack of plasticity of ordinary liquor soap of the present invention.

Portland cement mixtures used in concrete. This 5 The black liqu r soap may be d to the lack of plasticity makes it necessary either to cement prior toto during niixingbSmay be inuse larger amounts of water than would othercorpora'f'eH'H'iii'Tng"grindingof the ement clinkwise be necessary or makes for an insufiicient er. Care s ou e 9. en, 'however, to obtain a flow. In either event the concrete is not as dense uniform distribution of the black liquor soap and is not as satisfactory. A number of types as an uneven distribution may produce weak of compounds have been used in order to inspots. For this purpose when black liquor soap crease the plasticity of cement. Many of these is to be used as an addition to the cement during compounds, however, while increasing the plasmixing, it is advantageous to mix it with a neuticity of the cement mixtures have an adverse tral diluent such as kiesel r, fine sand, or th'e effect on the strength of the cement. In general, like, wmcfi makes it easier to o tain uniform displasticity is measured by a percentage of slump tribution of such small quantities of the maof a test cone. Practically 511 "compounds which" terial in cement work where small mixing batches have been used in the past to increase plasticity are employed.

have had an adverse effect on the strength. The invention will be described in greater de- However, unless the adverse effect is material, tall in conjunction with the following specific this is not of great importance and as a pracexamples in which the Portland cement mix was tical matter unless the strength of the cement made up as follows: either on '7 or 28 day strength tests is changed Example 1 more than 10%, the effect is not to be considered f i ti 1 i ifi b th Parts 0 any serous prac ca s gn cance ecause e 5 Portland cement 2041 factors entering into the strength of a given Sand (8 mesh) 6123 strength test sample of concrete even when Water 1210 using cement from the same lot, are suiiiciently "'f T complicated so that exact checks on strength are This ixture was divided up into a number not possible. For practical purposes, therefore, 30 of tion one of which was used as a control. any strength within 10% may be considered as To one batch there w added snide within the experimental error or normal variablack 11 1101' D- The te Showed n 83% t increase in sump over the control. At the A The present invention is based on the use of end of 7 days the change in Strength Was black liquor soap from the black liguor obtained 85 and after 28 days, -7% as comp r d t e y; 'as a waste roduct in the manufacture of kraft control for the Same length of t a r B the sulfate rocess. Black liquor soa is a cruge mixture of the sodium 4m; r0 Example 2 and similar resin acids an unsa ura e a y A further portion of the mix described in Exacids such as 0 e10, inoleic, and e like. Crude mple 1 was treated with 0.002% of Washed black Wafer so "l 'T a IS a so con aminated with cerguor snag. c e be en as in the first extain unsaponifiable materials such as hytosteramp e t a admixt as thomugh d Un ols and the like. K"'po'rti'on of the impurities in form. The mixture showed a 78% increase in c'rude black liquor soap maybe removed by washslump with a strength of a d ing with water, liquors containing sodium sulafter '7 and 28 days respective y. fate, and the like. What I claim is:

Black li uor soa either crudeclwashed is a 1. A method of increasing the plasticity of a powerful lasti'ci'zer; slump ncreases up to.420% Portland cement water mixture which comprises or more can be obtained by the use of 0.1% of adding thereto from 0.001% to 0.01% of black crude black liquor soap. However, when such liquor soap, said percentage being based on the amounts are used the strength is adversely afamount of dry Portland cement contained in the fected and according to the present invention wet mixture.

the amount of black liquor soap should be less 2. A Portland cement composition Co p 5 than 0.01%, preferably of the order of Portland cement having admixed therewith from Z 0.001-0.002%. 0.001% to 0.01% of black liquor soap.

1 Not only is it possible to use very small amounts of black liquor soap to obtain satisfactory in- ROBERT BEN BOOTH. 

